The timing of the development of the child

This has implications for policy and programme responses to the exploration and experimentation that takes place during adolescence. The characteristics of both the individual and the environment influence the changes taking place during adolescence. Younger adolescents may be particularly vulnerable when their capacities are still developing and they are beginning to move outside the confines the timing of the development of the child their families.

The changes in adolescence have health consequence not only in adolescence but also over the life-course. The unique nature and importance of adolescence mandates explicit and specific attention in health policy and programmes. It is also a time to develop knowledge and skills, learn to manage emotions and relationships, and acquire attributes and abilities that will be important for enjoying the adolescent years and assuming adult roles. All societies recognize that there is a difference between being a child and becoming an adult. How this transition from childhood to adulthood is defined and recognized differs between cultures and over time. In the past it has often been relatively rapid, and in some societies it still is. In many countries, however, this is changing.

But it is only one characteristic that delineates this period of development. Although the order of many of the changes appears to be universal, their timing and the speed of change vary among and even within individuals. These developments are linked to hormonal changes but are not always dependent on them. Developments are taking place in regions of the brain, such as the limbic system, that are responsible for pleasure seeking and reward processing, emotional responses and sleep regulation. Over the course of the second decade, adolescents develop stronger reasoning skills, logical and moral thinking, and become more capable of abstract thinking and making rational judgements. Changes taking place in the adolescent’s environment both affect and are affected by the internal changes of adolescence. These external influences, which differ among cultures and societies, include social values and norms and the changing roles, responsibilities, relationships and expectations of this period of life.

The appearance of certain health problems in adolescence, including substance use disorders, mental disorders and injuries, likely reflects both the biological changes of puberty and the social context in which young people are growing up. Other conditions, such as the increased incidence of certain infectious diseases, for example, schistosomiasis, may simply result from the daily activities of adolescents during this period of their lives. Many of the health-related behaviours that arise during adolescence have implications for both present and future health and development. For example, alcohol use and obesity in early adolescence not only compromise adolescent development, but they also predict health-compromising alcohol use and obesity in later life, with serious implications for public health. Adolescents are not all the same.

Adolescent development has implications for adolescent health. Adolescent development has health implications throughout life. The changes during adolescence affect how adolescents think and act. Adolescents need to understand the processes taking place during adolescence. To contribute positively, adults need to understand the processes taking place during adolescence.